1. Field of the Invention
The present invention relates to a treatment instrument for performing incision and coagulation treatment on a living body tissue by using ultrasonic vibrations.
2. Description of the Related Art
In general, an ultrasonic coagulation/incision apparatus is known as a treatment instrument for performing incision and coagulation on a target part of a living body tissue, etc., by using ultrasonic vibrations. The treatment on this target part is an act of any one of, for example, incision, resection, perforation, ablation, coagulation, and hemostasis.
As illustrated in FIG. 17, for example, the ultrasonic coagulation/incision apparatus is composed of a handle unit 2 to which a probe 5 is attached, and a transducer unit 3 which generates ultrasonic vibrations.
The transducer unit 3 is detachably attached to the handle unit 2, and is repeatedly usable if sterilization treatment is performed. A forceps-shaped jaw 15 for clamping a target part is provided at a distal end of the probe 5. At a lower part of the handle unit 2, there are provided a stationary handle 7 serving as a hold section for holding by the hand, and a movable handle 8 for opening/closing the jaw 15. An ultrasonic switch 11 for applying ultrasonic vibrations to the target part is disposed in front of the stationary handle 7. Incidentally, the hold section may be configured to be held at two points, which are the stationary handle 7 and movable handle 8.
In addition, the probe 5 is fixed to a rotary knob 6 which is provided in front of the handle unit 2. By rotating the rotary knob 6 in a predetermined angle range, a direction of opening of the jaw 15 is varied, and the target part is clamped and treated from a proper direction. In the transducer unit 3, a vibration element unit is mainly stored, and a cable (power cable) 50 is connected from the outside.
In this structure, at a time of performing treatment, if an operator rotates the rotary knob 6 and varies the direction of opening of the jaw 15, the transducer unit 3 also rotates. As a matter of course, since the cable 50 coupled to the transducer unit 3 also rotates, a twist occurs in the cable 50. Thus, the cable becomes twisted between the transducer unit 3 and a power unit (not shown). Normally, if a twist occurs in the cable, a force acts to reduce the twist, and the amount of a rotational force necessary for a rotating operation of the rotary knob 6 increases, leading to difficulty in operation. Furthermore, if the twist of the cable 50 increases, a winding state occurs in the cable 50, a force acts to reduce the substantial length, and the handle unit 2 is pulled and a shake is caused.
Besides, as illustrated in FIG. 17, in the structure in which the cable 50 is provided in a manner to extend from the transducer unit 3 to the rear (the side opposite to the sheath side), if an unintentional force acts on the cable 50, the treatment instrument is shifted, in some cases, such that the treatment instrument is pulled to the rear side (the transducer unit 3 side), and a slight movement will occur in the jaw 15 due to the shift. Thus, the operator will spend more labor in order to suppress a slight movement of the distal end of the probe 5 and to correctly apply it to the target part.